This invention relates to vibration damped rivet bucking tools of the type including a housing subjectable to a manual bucking force, a cylinder bore in said housing, abutment means at one end of said cylinder bore, a piston sealingly and reciprocally disposed in said cylinder bore and defining a damping chamber at the other end thereof, a rivet bucking die connected to said piston at said one end of said cylinder bore to form an assembly with said piston and applicable by said manual force against a rivet to be bucked, and passage means for supplying compressed air to said damping chamber to cooperate with said piston for transmitting said manual force thereto and to said die during rivet bucking.
In similar previous devices, suggested for example in U.S. Pat. No. 2,274,091, a counterspring, a relatively small air volume behind the large diameter damping piston and a small joint mass of the piston and die were apt to cause high and poorly damped forces in the housing. Furthermore no means were provided to adapt the bucking operation to variations in the work conditions such as variation in size and hardness of the rivets, the size of the holes, etc.